Sigmund bergman n



(N o Model.)

S. BERGMANN.

INSULATING PIPE GOUPLING.

Patented Feb. 5, 1889.

UNITED STATES PATENT OEEicE.

SIGMIND BERGMANN, OF NEV YORK, N. 'I'.

INSULATlNG PIPE-COUPLING.

SPECIFICATION forming part of Letters Patent No. 397,218, dated February5, 1889.

Application filed June I2, 1888. Serial No. 276,835. (No model.)

To all IN1/0m it 71mg concern,.-

Be it known that I, SIGMUND BERGMANN, of New York, in the county andState otl New York, have invented an Improvement in Coupling-Pieces, ot'which the following a speciiication.

My improvement relates to coupling-pieces employed to connect agas-supply pipe with a chandelier or xture used for both gas andelectric lights. In such chandeliers or lixtures it is desirable to soinsulate the joint that the electric current will not ground. throughthe gas-supply pipe.

In the accompanying' drawings, Figure l is a side elevation of acoupling-piece embodying my improvement. Fig. 2 is a vertical sectionthereof, taken through the axis of the gas-passage. Fig. 3 is ahorizontal section ot the same, taken on the plane ot the line n ar,Fig. 2.

A A designate two halves or portions ot the coupling-piece. These maybemade of metal-as, for instance, brass. Each is provided with a shankportion, a, and flanges a. The shank portions a are hollow andscrewthreaded internally to receive within one the gas-supply pipe andwithin the other the stem of the chandelier or fixture. Between theilanges a are pieces of insulating' material, a? a3 at. v The pieces a20.3 may be made of leather. The piece a is made of mica and is placedbetween thc pieces a? a3,

gas. It will be seen, also, that the metal adjacent to the insulatingmaterial is circumt'crent-ially fchamt'ercd, as at c c', providing anenlarged cavity, whereby a large surface ol' insulating material isexposed. Iv these means the carbonaceous or other material through whicha short circuit is effected has a much greater surface to forni overthan is the case in the old forni ot coupling-piece7 to which I havereferred, whereby a very much longer time is required to effect a shortcir` cuit, and the life ot the coupling-piece is materially prolonged. Bv placing a sheet of mica between the portions of insulating material o?a3 the com ilete im ireOnation ot` the l D Coupling-pieces forthepurpose specified have previously7 been made comprising the pieces AA and a piece ot' insulating material between them; but the insulatingmaterial has been so formed or cut away as to be iiusli with the bore ofthe coupling-piece, and being comparatively thin, the passage ot gasthrough the coupling-piece has caused a de- ,l

posit of carbon or other conducting material across the insulatingmaterial and between the portions A A', occasioning a short circuitresulting in a ground, or thc short circuit has been occasioned bytheimpregnation ot the insulating material with tarry matters or othersubstances from the gas.

In the example of my improvement illustrated in Figs. I, Q, and 3, itwill be seen that the pieces of insulating material a2 a3 extendinwardly beyond the wall ot the gas duct or passage of thecoupling-piece, so that acomparatively-restricted opening, b, is leftthrough the insulating material for the passage of the portions a? aiwith tarry or other conducting matters is avoided and the tendency toshort j circuit from this cause overcome.

The portions A A maybe secured together by screws g, passing throughinsulators in the ilanges a and the insulating material.

What I claim as my invention, and desire to secure by Letters Patent,is-

l. A couplingpiece comprising metallic portions provided withcommunicating gaspassages, and insulating material between said metallicportions extending inwardly beyond the walls of the gas-passages, saidgaspassages comprising an enlarged cavity ad jacent to the insulatingmaterial, substantially as specilied.

i. A coupling-piece comprising metallic portions provided withcommunicating gaspassages, and insulating material between the metallicportions extending inwardly beyond the walls ot the gas-passages, thewalls of the gas-passages adjacent to the insulating material beingcham'lered ot't, substantially as specitied.

A couplingpiece comprising' metallic jjiortions provided withcommunicating gaspassages, pieces of insulating material between saidmetallic portions, and mica between said pieces lof insulating material,substantia-lly as specified.

i. A coupling-picce comprising metallic portions having communicatinggas-passages enlarged at their inner ends, and insulating materialbetween said metallic portions, substantially as specified.

SIGMUND BERGMANN.

Witnesses: l

P. H. KLEM, .I r., JN0. F. GEIDEL.

IOO

